We have been snowbirds traveling from Washington to Arizona and back for about 10 years. Each year, we have stayed in the RV parks in Pismo Beach. We spend many hours walking the beach, shopping, and eating at the local vendors. Walking the pier is a must-do each visit.
I believe the restrooms are in a perfect spot right now. They are convenient for a quick stop during our many hours of beach time and pier fishing time for many others. They provide a place to wash off the sand and clean up before heading to the shops. They are close to the shops and restaurants, requiring very few in-town bathroom facilities. This central location discourages long-term vagrancy. The number of stalls seems to be sufficient as I have not ever had to wait to use a stall in the women's bathroom.
The exterior of the present bathrooms are clean and colorful and appear strong enough to stand many more years right where they're at. Sand corrosion is hard on all beach bathrooms—new or old. Money kept in reserve for upkeep of the present bathrooms would be a lot cheaper than replacing, moving, or adding new.