Hah, Kevin Smith caught some flak for that one:

" Someone called out Kevin Smith for this on one of his podcasts. According to Smith, on the day of filming, he asked if the picture really was a sailboat, and the prop master said no. When Smith started questioning this, the prop master said that a) it flashes on the screen too quickly for anyone in the theatre to notice, and b) VHS was too low-resolution for people to freeze-frame it to try it at home. So Smith let it slide.

Smith summed up, "Now, thanks to Blu-Ray, I get people pointing this out to me all the time!" "

https://www.reddit.com/r/MovieDetails/comments/9lf52b/in_the...