Market Wards vs AH

[Abriael]

You can't make an impulse purchase from a normal AH?

An impulse purchase is by definition something you weren't looking for, and that just appeared in front of your eyes and you bought.
An AH has no "windows shopping" system, so by-definition impulse purchases aren't part of the concept. You cannot just walk around an AH. You have to make an active search effort in order to have items offered to you.
That's not what an impulse purchase is.

you have to endure a load screen.

And you have to endure lists loading with an AH.