I've spent hours/days/weeks implementing algorithms or data structures from journal articles. No, you're not an outlier. A lot of times they don't include source code, even in the age of Github. Certain details or assumptions are often glossed over, and often the wording of a crucial technical detail is extremely ambiguous. Sometimes the only way I'm able to successfully implement the algorithm/data structure is through sheer luck - i.e. stumbling upon some piece of information elsewhere that gave me the necessary insight to understand what the author of the journal article meant.

I mean, I can understand academic time pressure and everything, but not providing a link to source code in this day and age is almost absurd. At the very least, it certainly doesn't encourage anyone to actually use your research in industry.