Most Helpful Guy
If the automatic tip is disclosed to you, then yes it is legal.
Many restaurants will have a statement in their menu that says "parties of 6 or more will automatically incur a 15% gratuity". If you eat there, you are legally obligated to pay the gratuity. If you don't see it, then too bad. If you don't want to pay it, go elsewhere.
If they do not openly disclose the gratuity, you are not obligated to pay for it. The exception is in touristy places, there the standard is that ALL establishments add a gratuity for non-local customers (locals often have proof that they live there, and waive the automatic gratuity)
Most Helpful Girl
Yes it is. At my work we only charge for grat with parties of 6 or more though. This is so ensure we get paid in tips for our hard work. It's a lot of work serving large tables and we rely on tips to make our money (we get paid under minimum wage!) for large parties we charge a 15% grat. For every bill/table, 3% goes back to the kitchen. If a table spends 200 bucks and doesn't tip I lose 6 dollars out of my pocket! So when someone doesn't too us a dime, we lose money working to serve that table. If you're upset about having to tip, don't go out. You are paying to get service. For anyone who's worked in a restaurant they understand much better that it's hard work especially in a busy restaurant like mine - working non stop rushing for 8 hours without a break. Im only working part time through school so I don't want to do it forever. Anyways hope that helps!