I met my girlfriend's parents for the first time a week ago. They are foreigners and were visiting the USA for the first time. Generously, they provided me with a surprise gift! It was a Mont Blanc fine liner writing instrument.
The "foreigners" background may explain some of this. In many cultures outside the U.S., valuable gifts are much more common for a variety of reasons.
One is that it shows the recipient that the giver is financially solvent. In many countries, particularly more third world ones, there are no credit reports you can easily run on anybody, so your "proof" of net worth is what you can afford to show off with. Since in many of those places written business contracts are rare, and often unenforceable, you have to prove you are credit-worthy that way before people will do business with you, or let you marry their daughter, which may be a more "business" transaction than we are used to in the U.S..
A second reason is that in many of those countries property and investment rights we are used to don't exist, or are recent enough that habits haven't changed. A good deal of family wealth in Asia, for example, may be in gold, because they never knew when money would be devalued, or bank accounts seized, or banks fail. Even in Australia I met a tour guide whose mother was broke because she had her savings in a bank that went out of business. No deposit insurance there at the time. My father-in-law's family lost their savings in German hyper-inflation in the early 1900s, and such things are not solely the province of ancient history, as the recent 47% haircut bank depositors took in Cyprus shows.
So while we, here, worry about putting our money to work generating more money, there are many other places in the world where you
hope to still have at the end of the day what you started the day with. Tangible, ideally portable, assets have a place in that investment strategy. :)
If you do marry her, you may want to do a bit of looking into expectations she and/or your in-laws have, they may be less impressed by a large bank account and early retirement than a big diamond ring and a Mercedes. On the bright side, they may be quite pragmatic about finances, and have a very good understanding of sacrifices for a goal.