Sadly the above posts are true in most cases...
Saying that we love you on the first date also means that we want to spend more time with you.
Just like you'd say... I love saunas... or I love

It's expressing that you really 'love' the feeling you get when with someone measured in units of time.
If you want to take off your knickers, well I suppose that's just more time spent with that person

haha