M experience of using m-gas - too expensive

I've been using m-gas for almost an year now... Yesterday, day they came to replace the  cylinder since it was below 2kg. 
Wakanikelesha sana..."mbona wewe hupikangi? Waeza kaa aje na mtungi 12months Bila kureplace?... Our workers need to be paid!" To cut the long story short they replaced.

I decided to calculate how much I pay for a kg of m-gas.

I had 39 bob in my account... the Cylinder was 13kg full... that's what the metre showed.

After my balance depleted... It switched it's self off as always.

I realized I had used 100 grams of gas... Which means... I spend 39x10 =390 for 1kg this also means I spend 390 x 6=2340 for 6kg of gas while my neighbors are refilling at 900 for the same amount of gas.
M-gas have a great business model... But they've got huge operational costs that they're transferring to consumers. 
If I'm not wrong... They're charging 350-390 per kg of gas.

While gas is retailing at an average cost of 900÷6=150 per kg

~ via Farmx