Keepsake

The sites I'm familiar with that give "increased drop" items/buyables are all the pay-to-win or "pay-to-reduce-grind" microtransaction variety. It's the type of site designed to force you to grind for everything to make paying more attractive.

If the whole point is to spend less time grinding for an item then buying the item directly makes more sense.

As for "anything of worth" a loot booster will also drop the value of all those "worthless" items even further.

Additionally, any loot booster would have to increase the odds of rare drops by over 10 times to make it noticeable to the average player.

For example, doubling the odds of a rare drop is a virtually invisible change. Let's take eggs.

Cribbed from here I'm averaging an egg drop every 9,450 battles (4.2 battles per minute times 75 minutes a day times 30 days) from the Mire. That's an average over the past couple of years so some months I get 0 and some months I get 3. Doubling the odds won't get noticed by me for 6-12 months worth of effort because it takes so long to get enough battles. Other venues will show it first (venues with fewer neutral monsters and higher battle per minute rates) but it will take weeks or months for those changes to start being noticeable without an announcement.

Increasing the drop rate by a factor of 10 means an average of 945 battles or 225 minutes or so of Mire grinding. To put that into perspective that's nearly 4 hours of grinding.

Given those numbers an individual player isn't likely to notice a change but in aggregate the site will. Generally we should see a slight decrease in AH egg prices but given how that won't affect the profit from spending that time in the Mire I could buy even more eggs with the same amount of effort and without buying the booster as long as enough other people do. This doesn't help people who get the booster, it helps people who can do the math.