I'm all about having a reference. Too many things in ol' Duder's head vying for brain cells, and I'd rather have the music in front of me and know I can give a good performance than try to look like I know it all and blow it because I missed a chord change or forgot a lyric.
PLUS...and this is a big plus to me...I like to play songs that the audience knows pretty well, and then get people out of the audience to come up and sing along, or grab a shaker or a tambourine (I probably don't have to mention there's often a bit of liquid confidence at play there). They have a lot better time if they can see the words and sing along, and they'll want to do it again, and pretty soon everyone wants to, and you've got yourself a hell of a fun time with crowd interaction.
Finally, sometimes people want to know if I can play a favorite of theirs. With my laptop, if I have an internet connection, I can usually dial up a tab and at least wing it enough for them to enjoy. I'm not great at ear training (though I keep trying to work on it). If the audience has fun, I'm having fun. That's about all that matters to me.
Oh, for those of you who go electronic, I just picked up one of these:
https://www.amazon.com/gp/product/B078Y4Q1HF. It's awesome for scrolling or page turning, and it works with Bluetooth on Android, iPad, or Mac or Windows laptops. Well worth the money.