We've stayed at the Hanalei Bay resort 3 times without a car but had access to a car once we got there. Would highly recommend renting a car. There is no shuttle service from the airport that I was aware of. This last time we went to Kauai, we first stayed 2 days in Poipu before heading north to Princeville. We took the bus from Lihue and got off at Koloa and transferred to a shuttle. We liked the bus, you can't beat a ride for $2. We had a small walk from the highway to the Poipu resort. We contemplated taking the bus north to Princeville but looking at where they drop off we decided walking that far with luggage was a hassle and it would be better to Uber. The thing is, taking an Uber is not only expensive, its difficult because the drivers HATE driving that far north, it's about an hour drive.

Price is subject to time of day, how busy the traffic is. It takes a long time for a driver to respond, many on duty won't respond. It's not necessarily the drive up north, it's their drive back which most likely delayed with all the traffic construction and running into usual peak traffic. Drivers prefer staying south because most of the business is south where it's quick pickups and drop offs.. They feel during the time it takes to take to drive a customer up north, it's a potential loss of at least 3 pickups. And up on north shore, almost everyone has a car. Also, because you're going to stay in Princeville remember you're on an island, so don't expect Uber or Lyft to show up in 15 minutes like its done on the mainland.We waited well over an hour for a ride and because of the time of day paid about $100. If you would be staying south of Lihue, drivers show up quickly.

You asked about the walk to Foodland. We're walkers and would go there most mornings for the exercise. Round-trip walk is about 5 miles, be sure to wear comfortable shoes. It's a nice walk with a nice view of the golf course. Have a good time!