The "land dirt" is something we dealt with. Our solution: a rug bungeed to the swim step. We also carried a two-step step stool, to more easily step up to the two rung ladder that was the factory spec.
We occasionally had issues with RV parks not allowing boats. Not a big deal, since there was generally another park down the road who would take our money.
We did this for the 8 years of our C-Dory ownership, traveling coast to coast to coast.
One more thing worth mentioning: RV parks are different from marinas in their allowance of gray water (water from your sink or shower - NOT from the potty)... if you put anything overboard in an RV park, you will likely be asked to leave. When doing dishes or washing hands, we put a dishpan in the sink to capture the water. Those of you with 25s that have a shower: yeah, you have to schlep to the RV park showerhouse so your showerbox doesn't send your shower water overboard.
On occasion, we would put up our bimini, sit in the cockpit, and enjoy the RV park ambiance... if you have a true RV, you know the pleasure of sitting under the awning, enjoying the same.
We did occasionally overnight in a Wal-Mart lot with the boat, but I don't care for that situation - if you have to leave, you have to go from the boat to the truck. Also, don't put any water overboard. Check with the store management to be sure overnighting is allowed (many municipalities have laws that do NOT allow overnighting anywhere but approved RV parks/campgrounds). And buy something from the store.
Have fun, travel safe,
Jim B.