I think there's a vibe out there in many cultures (including American) that being vegetarian/vegan or certain kinds of sympathy towards animals is unmanly and just kind of lame. This is probably more true in the right-wing demographic. I'm guessing this has been discussed in the animal welfare movement somewhere, so I won't attempt to delve into the issue further in this post.* Instead, I merely want to favorably acknowledge some commentary by comedian Bill Burr about boiling lobsters alive.
Bill Burr is a super-famous comedian and one of the most prominent cultural icons of masculinity in the U.S (perhaps in some respects the most prominent). Although I would say he is a party-neutral comedian, his comedic themes have included anti-wokeness and challenges to certain aspects of feminism, and probably has a huge following among working-class right-wing men.
Here is his commentary on boiling lobsters alive (6 min), excerpted from his podcast.
*Edit: Actually I will go into it for a minute. If anyone wants to see a great example of how to deal with this sort of thing in a different context, take a look at how Ford dealt with the issue of environmentalism/green-politics being considered soft, lefty, snowflake stuff when they wanted to advertise the fuel economy on their F150 pickup truck: "you won't be put in a chokehold everytime you fill up".
Yeah, in fact I think most of the domestic opposition also comes from this backlash (in poli sci it's called "negative partisanship"). The right starts to oppose animal welfare policy not on its merits but simply because the left supports it - another reason to strive not to polarize the issue.