This is it getting baked into the price.
Them increasing the size of the percentage-based cut suggests that the work Amazon does (logistics, selling access to the users' eyeballs) would be more sensitive to inflation than what the manufacturers and sellers do. Seems unlikely.
(I.e. what you're saying seems to be that for a $100 item that they charged $5 to ship previously, they will now be charging $5.25. Hard to complain about that.)
An example they give is of a small, standard 6-oz package where the fee will increase from $2.92 to $3.07.
[0]https://sellercentral.amazon.com/gp/help/external/GABBX6GZPA...
For fulfilment? That's extremely heavily dependent on three things: fuel, amortized vehicle costs, and labor. Major drivers of inflation before the invasion were tight labor market in the post-COVID rebound, vehicle costs, and fuel, and the invasion added further pressure on fuel, so, yeah, I’m going to say it's perfectly reasonable to expect that fulfillment costs have gone up in relation to finished consumer goods before fulfillment.
With logistics companies it's typically easier to identify the incremental surcharge, as at first glance they've blended it as fee increases.
I don't think that this is the case. If I sell XYZ product and my costs increased by 4% so I raise prices by 4%. Fuel costs for Amazon increased by 18%. The prices of the goods wouldn't necessarily offset what Amazon makes. And now you have to generalize this across all products they sell and all of their global logistical considerations...
I think what GP missed is that this price is likely going to get baked into the end-buyer price, but not by Amazon.
The reason it's likely not baked by Amazon is because Amazon's fulfillment has costs that don't get recouped until an item is sold. If Amazon moves seller goods back and forth through its warehouses, Amazon might never make the money back on the fulfillment service if the item never sells.
Sellers will wind up conveying this additional charge back into their item's price.
Same reason B2C companies do it all the time. While Amazon is notionally B2B, it's got lots of small sellers that probably behave more like consumers, and the business that don't just won't care how the price is characterized.
Amazon's business model is "skimming off the top." Essentially take x% of whatever. If prices rise due to external factors and Amazon's x% remains identical then their real-term income increase inline with inflation.
This is double-dipping. Prices rise, Amazon makes more, now they want "and 5% more" on top because reasons.
PS - Although this argument only applies to inflation adjustments, not fuel.
If it was a fixed increase, I'd be a lot less critical. But percentages piled on already percentage fee structures strikes of profiteering from their market position, and using the economic climate as a lazy excuse.
Dude, this is capitalism. Everybody uses every excuse, from the most justified to the least justified. Assuming it's greed is dumb, but assuming it isn't greed is spectacularly dumb.