Needed an "or" clause in cucumber to check either condition. Gripes: It's terse, but I don't love that it doesn't follow normal Matcher pattern, and that error string is built when we don't need it.

step_with_either_or.feature

Then the page should display either
    | Cat |
    | Dog |
    | Mouse |

step_with_either_or.rb

Then /^the page should display either$/ do |table|
    expect_to_have_content_any_of page, table.raw.map {|row| row.first }
end

def expect_to_have_content_any_of(element, options)
    fail ArgumentError, "expected to find any of (\"#{options * '" or "'}\") in \"#{element.text}\"" unless
        options.any? { |option| element.has_content? option}
end