I saw a half-dozen soldiers with automatic rifles stationed around Tienanmen Square. And (since some “grad” folks prodded me about this in the past) they were nowhere near government buildings. This is the same at several other locations I saw in Beijing. It was less common on Shamien Island, but Shamien is largely businessmen and tourists.
Whenever I saw a money/bank vehicle, there would be soldiers with what appeared to be shotguns. Hard to be sure, but they had the excessive-sized barrels I am only used to seeing in shotguns. I understand “protecting the money” (sounds much more capitalist than commy, just saying), but that was already more excessive than most countries.
To be fair, despite being pro-gun-ownership, I consider the US attitude of police officers carrying firearms at all times to be slightly excessive, so officers carrying the more intimidating weapons usually reserved for assault teams in the US is even more excessive to me. They seem to want very visible weapons for the same reason many of our left hate very visible weapons - the intimidation factor.