One theoretical perspective you could use to partially explain this is prospect theory (developed by Tversky and Kahneman). Specifically, the phenomena of loss aversion could explain the willingness to buy the more expensive option.

In marketing this topic would be approached through consumption values (http://www.sciencedirect.com/science/article/pii/0148296391900508 and http://libra.msra.cn/Publication/35004596/customer-value-and-autoethnography-subjective-personal-introspection-and-the-meanings-of-a). There are many different aspects in this choice, but should be explained through the value a consumer gets. Could be functional value (will not run out of space), social value (everyone around me are getting 128gb version) or that simply sacrifices for additional space are considerably lower than benefits (http://link.springer.com/article/10.1007/BF02894350#page-1). 

More than the traits, gender difference as identified in Neil Selwyn (2007), Hi-tech = Guy-tech? An Exploration of Undergraduate Students’ Gendered Perceptions of Information and Communication Technologies, wherein, "Boys are more impressed with getting a bargain and the thrill of bidding for things, where girls just want things therefore just go and buy it"

http://most.gov.il/PromotingWoman/Documents/Hi-tech%20Guy-tech%20An%20Exploration%20of%20Undergraduate%20Students.pdf

Any product that we buy is also a symbol; i.e it has a symbolic status. This phenomenon is called as conspicuous consumption in economics. The product demonstrates our status/prestige to others. The other way of looking at is that every product has two attributes viz. functional attributes and deterministic attributes. It is the deterministic attributes such as brand, packaging, advertising which influence the final purchase decision. We can also apply the concept of 'hedonic values'. The consumers' concept of what constitutes convenience and comfort has changed .  

Mr. Michael Steiner

I hope you serve something ...

First, we can locate as a motivational need for social recognition ( found in any theory of motivation ) .

Second, is the result of hedonistic symbolism, I'm studying 2 years ago , where being socially respected is a necessity, and it is an indirect way of relating to the rest and be accepted by them , but should generally occur in children under 9, but as the social symbolism is loaded with materialism and is associated with a brand , it can also occur in young or adults.

Some sources you can see are: O’shaughnessy y O’shaughnessy (2012) y Holbrook (1987)

Mr. Michael Steiner

I hope you serve something ...

First, we can locate as a motivational need for social recognition ( found in any theory of motivation ) .

Second, is the result of hedonistic symbolism, I'm studying 2 years ago , where being socially respected is a necessity, and it is an indirect way of relating to the rest and be accepted by them , but should generally occur in children under 9, but as the social symbolism is loaded with materialism and is associated with a brand , it can also occur in young or adults.

Some sources you can see are: O’shaughnessy y O’shaughnessy (2012) y Holbrook (1987)

Many of the individuals would not like to associate with the cheapest item in the market, because it is below their prestige to be seen with the cheapest product. Art the same they cannot afford a premium product they like. Thus they are willing to a little more for an enhanced/ or better brand product for satisfying their ego/ or we are superior to many others.