No, they just use this ticker for satoshis (1/100,000,000th parts of BTC). I created an LN invoice for 1000 SATS in Bitget wallet, and, when I tried to pay it via usual lightning wallet, my wallet was going to send 1000 satoshis (0.00001 BTC), not 1000 BRC-20 tokens.

By the way, the wallet I used for payment is Valet, which is also an open-source Lightning wallet:
https://github.com/standardsats/valet/releases/tag/4.4.1