I rode the BC bats until I hit exalted and got the hippogryph fron Cenarion whatever in Zangermarsh and used that on my priest until I got my RAF 2 seater rocket and used that until I got my Love Rocket a few years ago. When it came to land mounts, my undead priest proudly rode her raptor in vanilla because that shit was a feat within itself to get another faction's riding skill. When all races could ride the rest of their faction's mounts I ended up going with raptors on most of them for my Horde characters and Nightsabers on my Alliance side because I liked the looks of those. But there was some truth to the "summon my finest steed" in BC & Wrath because there were certain mounts that were 310 speed while everything else was only 280. If you had a 310 mount, you used that shit even if you didn't like the look of it.
Can't speak for SE but Blizzard offers several games that are 100% free to play that have regular monthly costs to run. Hearthstone doesn't cost crap to play or charge a monthly. D3 only costs a one time payment to buy then its free for life to play on their servers. Starcraft, HOT, OG StarCraft, COD MW, are all free to play and no subscription. Blizzard uses money from other games to keep those game going because there are people who want to play it.
I don't think you understand how you "buy with tokens" so I'll explain it to you. You use your gold to buy a token in the game. That token has a value of either $15 or $20 (don't know because I've only been on the selling end of tokens). When a player buys the token the set dollar amount is applied to their Blizzard balance immediately and turns into real life dollars in you Blizzard balance. You use that Blizzard Balance to purchase stuff from the store. Its that simple.