Decades ago the HOA of a 365 acre lake I went to every weekend would hire a guy and his folly machine to "crop the weeds". We always went spearing at night and I snorkeled often. The only difference I ever saw was lots of weeds floating after he made his runs for a week or so. I notice in the pics that what you said about wasted energy to operate is accurate. Also the amount of weeds going up the conveyer is minimal. I'm sure by the crews looks they are very enthusiastic about really doing a top notch job. My guess on disposal would be to dump in the lake somewhere.
However the fish story is encouraging. Think EVERYONE likes to see kids havin fun fishing. My grandbrats were out yesterday and the 10 yr old boy caught a 16" WE. First time any of em had seen a WE. I kept telling him to just lip grip it but he wouldn't. That GSF is certainly fat. Happen to measure it?

Do nature a favor, spay/neuter your pets and any weird friends or relatives.