I know it doesn't say it specifically - but the implication is there. "to love, to care, to hope, to live" all those things I equate with happiness in life. It's subliminal, and billboard advertising has done that for years. I also said I need spirituality in my life to be happy, not referring to how the billboard itself literally reads. I don't know what other people think, that's why I wouldn't presume to speak for them with a global "You don't need ....", but I would guess that some others might need spirituality and/or the good aspects of religion in order to be happy in life.
Not all people need these things, but some do - is all I'm saying. So, that billboard message is every bit as preachy as some religious messages. I don't need to be subjected to that kind of propaganda, from any side of the argument.