Can people be persuaded by anything other than an appeal to emotion?

I ask because the majority of objections to EA that I encounter are more emotional than rational, referring to the fact that humans care about things other than doing the most good possible, some selfish and some selfless (family, local community, pet projects ect).

Is caring on an emotional level about cost-effectiveness an essential part of EA? We like to think we're rational people trying to do what's best for everyone (without claiming to always perfectly achieve that), but do you think an emotional connection to that identity is a prerequisite to becoming an EA?

From the leading questions you can probably guess that I suspect this is the case, but I'd like to get a wider range of opinions.