... and this is true for basically every vendor, once you have any amount of scale. Including credit card processors. Yes, even that one with the really nice API. CDNs. Supposedly big cloud providers, but I've not used them at a scale where it was really worth negotiating (for either party).

Quick way to see if you can probably get one: email one of their competitors (a sales email address) and tell them what your average monthly spending with [current vendor] looks like, what your rates with them are, and emphasize that you're otherwise happy with them but feel like it might be worth moving if you can do significantly better on price. If you get back an offer lower than their sticker prices, ask your current vendor to match (assuming you're otherwise happy with them). Even someone who doesn't like and is kinda bad at negotiating can do that.

If they come back with no or trivial movement on price (a 5% discount or something can often be had if you just ask) and trying to sell you on features instead, you're probably too small still. Otherwise, enjoy the savings.