might be a silly question

I am looking to do kayaking trips with overnight camping in more primitive locations but i currently do not have anyone to go with. Is it possible to do “round trips” on these rivers as my car will be miles away from where these trips end up and walking down the highway with a kayak would suck

kayak shuttle
Try finding a local kayak company to do a shuttle for you. We did that on the buffalo River in Arkansas. They just drove our vehicle to the take out point for a small fee.

Paddle UP river first, then paddle back to your car.

Or, carry a bike lock, drive to the put in, lock up your boat, drive back home, and take a cab to the put in with your other stuff.

…check out the website…Meetup.com…there might be a group in your area and you can team up with other like minded people , unless your strictly interested in solo camping, and form a shuttle group. One other option. depending on a lot of things, is too use a bicycle to haul the kayak back to the put-in , such as surfers haul their boards on bicycles.Otherwise a R/T is the only way.

I did a 4 day trip alone on
the Missouri River. I got a friend to drop me off and another one to pick me up.

Depends on the current
If you can paddle, pole or line upstream then of course you can do round trips. If the current is too strong to work against then you can not.

Alternatives include outfitter or livery shuttles, bicycle shuttles, and portage carting. We just finished a 60 some odd mile trip. About 10 miles of that was cart portaging. Once you get the gear up to the road and loaded, cart portaging is as easy as going for a walk.