I never tried any of these yogurt before in my life. I guess the uhm or marketing tool to attract one isn't there.
When I think of Yogurt, I think of those Nestle yogurt which I can get in 7-11, a No-no.
But if a cup cost about RM 10 bucks based on the picture, I say it is reasonable, But if it's a self service, I doubt I can prepare it so well la..

I, myself is a coffee fan.
I drink Starbucks so often, I can say I spend more than 100bucks a month on it for RM 15-17 a cup
Now with a loyalty card (Starbucks card) I go there even more often, and working in a service industry,
I spend my clients Starbucks .With its loyalty card, (buy 10 free 1), I am actually getting my company to pay 10 cups, to get myself a free drink. A true marketing strategy.
I wouldn't hesitate to buy my clients coffee at all! That is my personal experience.

But if I am comparing a business model between a coffee and yogurt.
I would assume that (without any research done) coffee would bring more profit.

A coffee bean has a very long expiry date (1-2 years is possible if the pack isnt open) , if business isn't good , the beans wouldn't be easily expiry,
I am not sure about Yogurt or fruits, How long can the ingredients last? If its a few months, then calculating the orders is very important.
Well overcharging is definitely a good way to cover waste

A handful of coffee beans can sell a cup for RM 10 - RM 15 bucks. I say the gross profit is definitely very high,
Labor wise, it is the same, both need a cashier and someone to refill stock or brew. Stabucks only hire 2-3 pax per shop per day.
Rental cost are the same, renovations cost, varies. But I like Starbucks better in it's interior.
What about Yogurt? What is the gross profit per cup? How many cups needs to be sold to cover the overhead cost?

In terms of market target,
I've just read about 5 pages of the forum, and I can say about 70% isnt willing to return because it is overpriced, meaning not much are willing to spend personal income on Yogurt.
If targeting healthy people, why not Salad or Gelatomio ice cream? The rum and raisins is soo good
If you are targeting working people I would definitely bring my clients to Starbucks to discuss business models instead of Yogurt.
Maybe, I feel safe and professional to bring client to discuss business over coffee compared to Yogurt.
Never hear someone discuss business over Yogurt before.. it sounds weird, maybe I will check the stall one day, but if its self service, its worst.
You don't want yourself to go over the counter and get messy. I prefer to order and wait for my F&B to be ready than making a mess myself.

Those are my feedback, well business is business, with the right location and even if Yogurt can only capture a small amount 0.001% of market in a highly populated area,
Who says it cant make money? After all it's a take-away business, you don't need a huge space to gain profit.