There's many lakes that you can't have internal combustion engines on. These aren't ESA issues, they're all real small lakes that they wanted the guys with the small boats to enjoy some peace and quiet.
Nothing like a nice quiet morning on the lake and here comes some schmuck to the boat ramp with his gas trolling motor and continues to troll all day. I could see it if it were a big boat but they're always in 12' V hulls.
C'mon you can get a decent elec. motor for a little boat now for around $100 or so.