At least this game and the one's you mentioned have been releasing stuff every few months. While summertime does have an "ending", though you could honestly argue if it does or if the dev just said this is the ending deal with it, it's been what 3-4 years of the tech update now and looking to be another 1-2 years for it to hopefully be done and the last released update was a year ago or so though it was frankly supossed to be done 1-2 years a year ago so who knows. The update speed has frankly just gotten slower even after giving out no new content.
It would be one thing if the dev just said the games done now just gimmie money to support but the dev keeps saying they will hire more ppl at milestones but hasn't for years, keeps saying the tech update is needed and after being done will release more content more easily, like the reason for the update was for better graphic/widescreen and making it easier/faster to churn out content but now makes a ton of money each month so has no reason to stop keeping the game as not being "finished".