Why can't religion be fun?

I just read a quote from Joanne Woodward
"sexiness wears thin after a while and beauty fades but to be married to a man who makes you laugh everyday, ah, now that's a real treat"

I would think the same would be true of religion.  OK, as I see it, religion is the practice of a formal relationship with the God source.  Being the source, God created fun, happiness and laughter too.  So, why when we go into churches and places like that we are so stoic and solemn?  I understand being reverent, but can't we be joyfully reverent?  Wouldn't it be so much easier to maintain a relationship and be married to a God who makes you laugh everyday?  Instead of counting our sins, couldn't we count our joys?  We could pledge to increase our goodness.  I would so enjoy a confession of blessings and gratitudes with a promise to go forth and do more -