Large chunks of Agricultural Land for Sale

While looking at the internet and newspapers, for buying Agricultural land, I found that there are sellers selling large chunks of land (100 Kanal Plus) in the districts adjoining Islamabad. I wondered to myself as to what the purpose could be. It certainly isn't for Agriculture since the asking price (2-5 Lakhs/Kanal) makes little economic sense given the fact that this is a Barani area and current prices of agricultural produce (particularly wheat) does not make sense.

My question is therefore as to what is the purpose of offering such large chunks of land. Is it with the hope that some speculative player would invest in buying their land. Is there something else that I have missed.

Thanks in advance.

AH

Let me ask a specific question.

What is the rate of colonization of land in and around Islamabad particularly towards Taxila. This would include Multi Gardens, WAPDA Town, AJK Society.

Also is their construction going on in the area around Fateh Jang airport?

TIA Aurangzeb