Unfortunately, yes. Keep in mind that in text any vocal tone and visual clues are lost, and a lot of sarcasm is signaled those ways, so some additional indication in text is useful.
Also, Poe's law is alive and well here. You assumed it was sarcasm, but I'm not so sure. It's not too far fetched for me to imagine someone thinks mashing up bugs to spread on a plastic bag is horrible. See my first paragraph for the solution to this...
Oh sure because satire wasn't commonplace in books long before the internet. How would those poor souls have figured it out it wasn't serious?! IMPOSSIBLE.
Regarding Poe's law, if it looks like sarcasm assume it is and move on, but I understand that commenting on the internet is of utmost importance and a task that shouldn't be taken lightly.
Also, Poe's law is alive and well here. You assumed it was sarcasm, but I'm not so sure. It's not too far fetched for me to imagine someone thinks mashing up bugs to spread on a plastic bag is horrible. See my first paragraph for the solution to this...