Don't know which way to side here. On the one hand have tendencies to agree with the bug eyed fuzzy creature's post above me.

On the other, I agree with you OP. Megacorps tend to be scumpools. Ethical and moral quagmires and blights on humanity. Deep dark vortex's of greed, selfishness, many other assorted lowlife behaviors. Favoring tyrannical practices that run roughshod over the common good as SOP and general corp policy. Init grand ?
While still on the next hand ( if you've been keeping count, I'm up to three hands so far.) It's Google's toy, they aren't forcing you to use any of the resources they provide and it's not as if they give the slightest whit whether you use LM's branded search or not. In fact I'm confident in saying the reason they imposed the stipulations on LM to be eligible for payout in including it in the 1st place. Is cause Google Inc knows the LM branded search isn't going to be well recieved. It's kinda annoying imo. So they are hoping thereby to compel LM's userbase to switch to another web browser. aka: Esp chrome/ium.
Then they don't have to pay anyone anything and get additional benefits from having an increased share of the browser market directly.
On yet this hand.

Yep ... no doubt there are several alternatives to generate revenue for LM. For whatever reason(s). Those aren't being implemented, the people behind this gnu/nix distro have a lot on their plate and are apparently not digital marketing experts or aces at monetizing web traffic or their users. They'd have to study Google if they wanna learn from one of the best when it comes to that subject.

Last hand ... I promise. Alternative for you, if you wanna financially show support or appreciation for the software LM HQ produces, maintains ... distributes ? How about a modest donation occasionally ? Or if you mean ... LM HQ turn their backs on a revenue source they've found cause you're ticked off at the buttheads over at Google HQ. Perhaps come up with some good alternatives and alternate options for them and contact LM HQ with em ?

edit: Disclaimer: I am in no way officially assoc with the LM proj. The following is my opinion and random babbling. The folks at Mint HQ have nothing to do with the opinions to follow.
Occurs to me, if you want to punish the mighty Goog, then you might actually consider using LM branded Goog search ... MORE. They have to pay LM summin probably whenever a sponsored link is clicked. Thereby taking money out of Goog's pocket. Though am sure Goog's accounting dept knows how to write anything and everything off and probably like most major corps don't pay a dime in taxes and actually make money on losses ... errrr. Anyway, like say if you wanted to visit M$ sponsored links ... Then you'd be kicking two sleazeball megacorp's in the buttocks with one click.