I wish SE...

I wish make the special limit time sale for a cheaper account-wide mounts

or offer the option to purchase the single character version for them [even if it a limit time sale it is still good].

The price for the account wide version isn't tempting for people who have only 1-2 characters.

They do on occasion put them on sale among other things, they're just not "cheap" even then. If they really want to make some cash they should price them lower imo, especially when there's a sale.