But if you’re doing it anyway may as well get the free stuff from it.

Counterpoint: By using the app, yet another organisation has your personal details, phone number, email, payment method including possibly credit card details. Do they have your birthday too? That's plenty enough data to attempt identity theft.

The app also tracks all your purchases. Loyalty cards are used to do this too. Looking at your purchases someone could reliably predict what days and times you are buying your coffee. So, they also know when you aren't at home, Thieves would love this information and could plan a little visit to your home to relieve you of some of your valuable items.

Companies make money by capturing your data, using it internally, but also by selling it too. You probably don't know if, what or who they onsell it to.

Finally, as we"ve seen companies' data is constantly hacked (eg Optus). There's little or no penalties for companies not taking good care of your personal information.

This is just off the top of my head. But it's the generic "Reasons why you shouldn't use an app" that are usually ignored. It's ultimately a trade off between security and convenience/cost.

Yeah it's legit a great app. Regularly get great offers on there like a $4 medium meal, $1 large frozen coke, $1 hash brown, $2 mcflurry, etc - and the points you get for spending any money aren't ridiculously pointless like most are.

Cheaper (and tastier) to get a thermos and make coffee at home. Also, the food might seem cheap, but you can meal prep with things like rice, beans, and frozen veggies for much less money (and time actually). Alsooo Maccas will slowly kill you.

Don't like raining on your parade, just trying to help people save money and live happier lives. McDonald's won't save you money in the long run, and it will screw up your body.