It feels more like a religious interdiction than a utilitarian decision
There are reasons why religions tend to have rules, rather than e.g. just saying “whenever you have a decision to make, consider deeply which option seems like it would please the gods most and do that”. One of those reasons is that while following the rules may be challenging, applying deep consideration to every single moral decision would be pretty much impossible. Another is that if you allow yourself flexibility then you will probably overuse it. Another is that if you are known to allow yourself flexibility then others won’t know when you’re ignoring the rules, reducing the power of social pressure to help you keep them.
If you happen to be (1) unusually smart (hence, better able to apply deep consideration to individual cases without getting overwhelmed) and (2) unusually principled (hence, better able to resist the temptation to abuse flexibility) then, indeed, you may well do better to be flexible about your rules. (But, of course, everyone likes to think they’re unusually smart and unusually principled, especially when thinking so offers the prospect of more freedom to bend your moral rules.)
I agree with you that many vegetarians’ values would be better maximized by being flexible about their non-meat-eating in some circumstances like the ones you mention, if we consider each occasion in isolation. But it may still be a better value-maximizing strategy to have a strict policy of not breaking the rules.
(For the particular cases you describe, where a vegetarian’s self-imposed rules are inconvenient for other people, there’s a further consideration: they may want their vegetarianism to be highly visible, in the hope of making other people consider imitating it. Their relatives may think “bah, how selfish of them”—but they may also think “wow, they’re really serious about this; perhaps they may actually have a point”.)
There are reasons why religions tend to have rules, rather than e.g. just saying “whenever you have a decision to make, consider deeply which option seems like it would please the gods most and do that”. One of those reasons is that while following the rules may be challenging, applying deep consideration to every single moral decision would be pretty much impossible. Another is that if you allow yourself flexibility then you will probably overuse it. Another is that if you are known to allow yourself flexibility then others won’t know when you’re ignoring the rules, reducing the power of social pressure to help you keep them.
If you happen to be (1) unusually smart (hence, better able to apply deep consideration to individual cases without getting overwhelmed) and (2) unusually principled (hence, better able to resist the temptation to abuse flexibility) then, indeed, you may well do better to be flexible about your rules. (But, of course, everyone likes to think they’re unusually smart and unusually principled, especially when thinking so offers the prospect of more freedom to bend your moral rules.)
I agree with you that many vegetarians’ values would be better maximized by being flexible about their non-meat-eating in some circumstances like the ones you mention, if we consider each occasion in isolation. But it may still be a better value-maximizing strategy to have a strict policy of not breaking the rules.
(For the particular cases you describe, where a vegetarian’s self-imposed rules are inconvenient for other people, there’s a further consideration: they may want their vegetarianism to be highly visible, in the hope of making other people consider imitating it. Their relatives may think “bah, how selfish of them”—but they may also think “wow, they’re really serious about this; perhaps they may actually have a point”.)