stop multiplying dice together

thinking about dice too much has made me care about a thing that doesn't matter but it bugs me when i see it sometimes and now i will share this anxiety with you.

say you want a number between 1 and 144. so you roll 2d12s and you multiply them together. that'll give you a nice flat spread right?

nope:

(using anydice.com)

if you want to do like a d100 thing with d12s, you have to do (d12 *12)-12 + d12-1

which is a little too complicated to ask of somebody at the table. if you had d12s marked like d10s (from 0 to 11) it'd be more straightforward but basically just don't multiply dice together, it makes a really noisy graph that trends low.

how important is this? somewhere between not important at all and maybe very slightly important. if you're rolling monsters with lots of hit dice this way you skew the results in the players' favor.