I doubt there is any router on the market today that operates on 2.4 Ghz by default. Some don't even have it as an option. So everyone with a Wi-Fi network in their house is already using the 5 Ghz band. And while range is a problem (in a lot of cases it isn't, considering modern city apartments are tiny and walls are made of cardboard), having multiple access points doesn't really fix it unless you have them scattered literally every few meters in your house. Heck I'm pretty sure I won't get a 1.5 Gbit/sec connection even if I put my router on the same table as my laptop.