Not everyone has the same amount of savings in retirement.
Some people amass a considerable amount of wealth.
So if you are one of these people, what else are you going to spend it on besides a nice property, especially in a country where properties are much cheaper than back home?
If you don't want to take the risk of losing the property to a Thai woman, then the only other option is to travel extensively. Then even if the relationship ends badly, at least you had some fun times together traveling the world so it won't feel like you've been scammed.
Otherwise, anyone with substantial savings in retirement will be tempted to buy a nice villa at some point. Who wants to sit on cash in a bank and have a crappy apartment?