In 2010, a California grey whale washed up dead on the shores of the Puget Sound. Autopsies indicated that its stomach contained a pair of pants and a golf ball, more than 20 plastic bags, small towels, duct tape and surgical gloves. (Clean Water)
One thing that I really do not understand is how in the world and why hotel guests just take their hotel towels to the beach and leave just them. Here in Mission Beach, San Diego, you find them in trash cans, in parking lots, at picnic tables, on the beach, burned in firepits, washed away in the surf and in trash cans. The unusual day is a day without towels. Currently I have over 60 Hotel Towels waiting to be sold or donated. 
These are not ‘cheap’ towels: Marriott, Hyatt, Hilton, Omni, Bahia, Sheraton and of course other hotels. This does not even include the blankets, sheets and even pillows. I am Not Kidding You. In 2013 when I was picking up beach trash somewhat, I donated 269 beach towels and again in 2015 (another beach trash time), I donated over 200. That does not even count the ‘good’ beach towels I gave away to friends and family. This is only the white hotel towels. 
11 Reasons Why Not To Leave Your Towels At the Beach
1.) Textiles (non-organic) are one of the most pesticide using materials in the world. Can you get rid of pesticides in fabrics? To find out the answer visit EcoTextiles ‘In the U.S., cotton ranks in third place in terms of pesticide use after only corn and soybeans. More than 38 million pounds of pesticides were used on cotton in 2014. The same year, cotton ranked fourth in terms of fertilizer use on crops – almost 973 million pounds – behind only corn, soybeans, and wheat’ (Source) All those pesticides go into our drinking water and food sources. To continually throw them away only adds to increase overall production and thus more pesticides.
2.) This is theft: Whether the hotel charges the guest or not, who knows, but what we do know is that this is technically theft. The people that leave them behind are thieves and once a thief… are you always a thief?
3.) Adds into the cost of hotels. Hotels do not give away much. The theft is absorbed into the room cost. Each of us will pay for this down the line.
4.) Shows lack of respect to the beach, the city, the hotels, other visitors and the Park and Recreation Department who has to clean up your trash.
5.) Sandy and food stained towels attract flies, fleas and other flying pests.
6.) It is wasteful: You don’t want the towel, shake it out and return to the owner. Take it home and donate it, homeless shelters, battered women shelters, humane societies, orphanages need towels desperately. When I told friends of mine in Mexico how much towels I pick up on the beach.. they were … send me.. the Senior Center needs, the schools need, the Spay Program needs, the orphanage needs. If I sent down 200 towels to Mexico, they would be gone in 20 minutes.
7.) What does it teach children? That everything is disposable? There is no need to recycle or reuse? Property is cheap? Lack of consideration?
8.) Whenever towels are left like this on the beach, the beach cleaners have to stop, get out and clean up the mess. It takes time, that time can better be used to clean other parts of the beach, which do not always get cleaned because they have to continually stop and pick up the messes.
9.) Not only do towels take up valuable space in trashcan which are already overflowing. They take up space in landfills. Into the landfill and seeping toxic substances. How fun is that?
10.) They kill Marine Animals.
11.) It shows a lack of responsibility for ones own action.
All of the said, May 25, 2018 is National Towel Day. This day is a tribute to the author Douglas Adams by his fans. On this day, fans openly carry a towel with them, as described in Adams’ The Hitchhiker’s Guide to the Galaxy or share their folded animal towels to demonstrate their appreciation for the books and the author (Wikipedia) No need to take your own towel, just go to the beach and grab a few!
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