I'm not sure about that. Mazda would have to prove that the aftermarket oil filter caused the damage that led to the warranty claim. Even if the filter was not at fault, who needs the hassle of fighting it. Mazda filters cost the same as any good filter, and they even come with a new oil drain plug gasket in the box.
And SkyActiv-G 2.5T uses different oil filter from the SkyActiv-G 2.5L on OEM; but on aftermarket all use the same oil filter. Mazda could use this as the excuse to refuse the warranty service on oil consumption problem, even though the oil filter should have nothing to do with it.
BTW, the free aluminum drain plug washer usually is a throw-in by the parts guy, they should charge you ~$1 for it.
I just changed my oil today. After 5000 miles the level was right at the full mark with warm oil. I put in 5-1/2 quarts. The oil level should be at the full mark to start.
The oil capacity spec by Mazda says 5.1 quarts for oil change on the 2.5T. If you need 5.5 quarts, who is right on this?
The question remains...where is the oil going? It isn't disappearing. Wherever it's going it is either making a mess or being burned and creating carbon that can cause a problem. I'd closely monitor the consumption, then get on the dealership to be in touch with Mazda North America to get it fixed.
In the case of my previous VW Passat 2.8L V6, I didn’t see any sign of blue smoke even though the engine was burning 1 quart of oil per 800 ~ 1,000 miles. Since VWoA refused to replace or overhaul the engine, and I didn’t want to keep pouring in 5W-40 full synthetic oil with risk of damaging 2 expensive catalytic converters, I chose to get rid of it early at 56K miles.