Maryland spent multiple millons of tax dollars on the earlier reproducing snakehead incident. This year already thay have had to drain another pond, as an angler caught another snakehead, more millions down the drain. A branch of the Potomac river in VA near DC had yet another snakehead caught by an angler within the last week. More megabucks will be spent monitoring that watershed.
At least locally, if you get caught introducing non-natives into native waters, you are liable for all clean-up costs - so if you don't have a few million in spare change, do not even think about it.
Releasing non-natives is a wonderful way to get the aquarium hobby banned.
Tropicals can survive and out-compete natives in many areas - downstream of power plants tend to be hot spots, not just for water temps, but for survival and multiplication of non-natives.
Dumping pets of any sort is stupid, malicious, and expensive to all the rest of us - even disregarding the damage to the native species.