What if the developer decided to shut the game down and abandoned it ?
Possible, but doubtful.
There are exceptions to the rule (but only a few), but for the most part the devs that embrace this forum do quite well. There is no other place on the planet where a game can be tried by tens of thousands of potential customers. Devs that interact here, that answer questions here, that see this as a publicity site instead of a 100% pirate site are usually rewarded. Keep in mind that they want people to essentially purchase a game based on the possibility it might get finished some day. But there are those like me who don't really like that business model and want something tangible for my money.
All the years I spent in video production I never ever billed someone up front...to do so I would have been laughed at. I had to secure financing and loans for equipment and gamble that those would pay off in the long run. With the patron model, the dev has little risk involved, so frankly I don't understand why some of them are so antagonistic about this forum. Being positive and allowing word of mouth to generate more customers is a solid bet. I can point to games that started here with only a handful of supporters that have now grown to hundreds. Then, after a good run with one game they go on to a solid base for the next project. Patience and good will go a long way. With impatience and antagonism, they only make it more difficult for themselves.