His comments came on the back of prop Kane Evans' spectacular charge on Bulldogs forward Sam Kasiano in Friday night's match, which earned the Rooster a warning but not an official reprimand.
The Cronulla back-rower said he hopes clean shoulder charges like Evans' will be re-introduced, but said the dangerous ones should be punished severely as a deterrent.
"I just think they should bring it back to be honest with you," he told Sky Sports Radio.
"I just think, if you're going to shoulder charge someone and it's going to go wrong and you hit someone in the head, they're going to have to mark it really, really hard and give you weeks on the sideline.
"If it comes off like the one on the weekend, well, you know, play on."
Gallen acknowledged the charge is a "risky play", but said the mandatory penalty for all shoulder charges on the field was especially disadvantageous for NRL teams.
"A penalty in Rugby League is big these days, especially from the kick, gifting a team field position coming out of their own end," he said.
The Sharks are riding high in fifth after four successive wins, including a 18-14 win over the Warriors in Auckland last weekend.
Gallen said the team was finally playing at its true level.
"It's not all that impressive to us internally, in the camp, we just think we're getting to where we should be," he said.
"We know we're good enough to play semi-finals football, and we've got a good couple of weeks coming up which will really test us."
The Sharks will come face-to-face with the equal-first North Queensland Cowboys at Shark Park on Saturday.
