You evidently have been fortunate enough never to have been around a human cadaver that has been dead for any length of time. If you had, as I unfortunately have, you would not ask why they buried them, and flowers seems a natural way to try to cover up the putrid odor.
Hank
http://hrsbstaff.ednet.ns.ca/waymac/History%20A/A%20Term%201/2.%20Origins/Neanderthal%20Notes.htm
One of the most fascinating and controversial burial sites is the Shanidar Cave. The remains there, called Shanidar IV, were carefully placed in the fetal position on a rough bedding of woven woody horsetail, a type of local plant. According to the pollen samples taken, this Neanderthal was interred with several different species of flowers. "From the orderly distribution of grains around the fossil remains, there is no question that the flowers were arranged deliberately and did not simply topple into the grave, as believed, as the body was being covered" (Leaky and Lewin 1977:125). Apparently, the family and friends of the deceased gathered these distinct species of flowers, carried them to the grave, and carefully placed them on the body. Some of the flower specimens found with Shanidar IV were yarrow, cornflowers, St. Banaby's thistle, groundsel, grape hyacinths, woody horsetail, and a kind of mallow. Many of these have medicinal qualities which "range from relief from toothache and inflammation to uses as poultices and for spasm" (Solecki 1971:249). According to Solecki, "one may speculate that the individual was not only a very important man, a leader, but may have been a kind of medicine man or shaman in his group" (Shreeve 1995:53). From this analysis it is likely that the "Shanidar people were aware of at least some of the medicinal properties of the flowers is not unlikely" (Leaky and Lewin 1977:125).
This skeleton showed that he had been buried lying on his back, slightly inclined towards the left, with flexed legs. Three flat stones, were associated with the burial, one near the skull and the others on the arms, and various incised large bones, bone splinters, and flint flakes had been put in his grave, the former often being interpreted as protection for the burial. Near the male grave was the skeleton of a woman aged between twenty-five and thirty, buried in a such a position to suggest that she might have been tied up before burial. No grave goods accompanied this burial. Neanderthals three and four were buried in trenches both 30-40 cm deep and very similar in appearance. They contained the bones of two (possibly three) children and one fetus or neonate. Amidst the sterile trenches was one oval depression, 40 by 30 cm, which contained the remains of an incomplete foetus (aged about seven months) and three beautifully made racloirs. (Shackley 1980:87)
The burial site of the "Old Man," at La Chapelle-aux-Saints, was of vital importance in the growth of ideas about Neanderthals during the turn of this century. This individual was buried on his back, with his head to the west, the left arm extended and his legs flexed to the right. Next to the head were three long bones of a mammalian metatarsal, along with other animal remains. Many of these bones appear to have be burnt, as well as the surrounding sediment, which could possibly represent some feast that took place before this individual was buried.
What are you doing next weekend? I will supply the beer!