Do Audio Interface manufacturers use A-weighted Measurements to make specs look better?
Most audio interface devices are built for the commercial electronics industry which produces devices to be used by people to listen to music, radio, TV etc; for multimedia reproduction purposes.

Therefore the commercial electronics standardisation organisations, suggest or enforce the use of a number of frequency weighting filters (A,B,C etc.) for getting more relevant results for the technical specs involved, considering that human beings will be the final consumer of the audio end result. It's not applied for getting an illusive improvement of the numbers (mostly SNR), but for providing an acceptable performance at the lowest cost.

If your purpose of audio (acoustical) interaction is some engineering or scientific measurement and computations, then look for the unfiltered (bare) specs if available. You may ask manufacturers to provide you those numbers, if possible. But most would restrain from disclosing that information due to confidential reasons...