ITT: stuff that annoys you and limits your choice in certain sets

>Articuno and Dragonite get Heal Bell as a purification move in XD, but not from the move tutors in HG/SS/B2/W2
>Pinsir learns Double-Edge from a move tutor in gen III. Heracross and Yanma meanwhile got it as a breedable move, but not Pinsir, the only one that could actually make some use of it
>Aerodactyl has Rock Head, meaning it could use Brave Bird and Head Smash with no worry. Not it gets Tough Claws as a Mega, further boosting those two attacks. However, it still doesn't learn either of those moves, while Crobat gets Brave Bird (despite the fact that it is a mammal), and Archeops gets Head Smash (not to mention Archeops is more of a bird than Aerodactyl, and yet Archeops belongs to 2 egg groups (that's how it gets Head Smash), while Aerodactyl only belongs in the Flying egg group).

>inb4 why would you want to use Heal Bell on Dragonite
I wouldn't, but it's kinda silly to think they made the move available on a specific situation but not on a general thing like a move tutor.