If you're "tired of explaining it" then gain a better understanding of what you're talking about, unless you're claiming that the Chinese are putting 13C+ rated
batteries in their 510s (2.39A @ 180mah = 13.277 "C")
The "C" rating is a ratio comparing the capacity of the battery and the current draw placed upon that battery. It describes the current draw that the battery can provide in a stable manner - that's it.
If I have a 1000mah battery and I put a 1 amp draw on it, that is a 1C rate and the battery will drain in an hour. If I put that same 1 amp draw on a 500mah battery, that is a 2C rate and the battery will drain in 30 minutes.
If I put a 1 ohm load on a 5v battery, it is going to draw 5amps whether that battery was designed for a 1C rating or a 1000C rating. The only difference is going to be the stability of the battery at that discharge rate.